First medical device for treating ADHD approved in US

In a first, a medical device that can treat attention deficit hyperactivity disorder (ADHD) through mild electrical pulses has been approved for use in the US.

The US Food and Drug Administration (FDA) permitted marketing of the prescription-only device, called the Monarch external Trigeminal Nerve Stimulation (eTNS) System, last week.

It is one of the first non-drug treatment of its kind to be sanctioned by the FDA and is suited for patients aged between seven to 12 years of age, who are not under prescription ADHD medication.

ADHD is a common neurobehavioural disorder that begins in childhood. The symptoms include difficulty in staying focused, paying attention and controlling impulsive behaviours.

The diagnosis of ADHD requires a comprehensive evaluation by a health care professional. For a person to receive a diagnosis of ADHD, the symptoms of inattention and/or hyperactivity-impulsivity must be chronic or long-lasting, impair the person's functioning and cause the person to fall behind normal development for his or her age.

The Monarch eTNS System is intended to be used in the home under the supervision of a caregiver.

The cell-phone sized device generates a low-level electrical pulse and connects via a wire to a small patch that adheres to a patient's forehead, just above the eyebrows, and should feel like a tingling sensation on the skin.

The system delivers the low-level electrical stimulation to the branches of the trigeminal nerve, which sends therapeutic signals to the parts of the brain thought to be involved in ADHD.

While the exact mechanism of eTNS is not yet known, neuroimaging studies have shown that eTNS increases activity in the brain regions that are known to be important in regulating attention, emotion and behaviour.

"This new device offers a safe, non-drug option for treatment of ADHD in paediatric patients through the use of mild nerve stimulation, a first of its kind," said Carlos Pena, director of the Division of Neurological and Physical Medicine Devices in the FDA's Center for Devices and Radiological Health, said in a statement.

The therapy should be administered only under the supervision of a caregiver, during periods of sleep.

Clinical trials suggest that a response to the treatment using the eTNS requires up to four weeks to become apparent. The FDA recommends that the patients should consult with their health care professional after four weeks of use to evaluate treatment results.

The Monarch eTNS system's efficacy in treating ADHD was demonstrated in a clinical trial wherein they compared eTNS as a sole treatment as opposed to a placebo device.

A total of 62 children with moderate to severe ADHD participated in the trial and used either the eTNS therapy or a placebo device at home for four weeks.

ADHD rating scales (RS) were used to access the severity and frequency of ADHD indicators. A higher score is a sign of worsening symptoms.

The researchers concluded that at the end of the four weeks, the ADHD-RS scores decreased in the active group and there was a significant improvement in their ADHD symptoms.

The few side effects observed with the use of the eTNS therapy were drowsiness, an increase in appetite, trouble sleeping, teeth clenching, head aches and fatigue. No adverse effects were reported with the use of the device, FDA said in a statement.

The FDA warns that people who use implantable pacemakers, neurostimulators or body worn devices such as an insulin pump should not use this product.